In prior art medical/surgical systems, the interface between a directional caster and a supported structure was typically done with a keyed caster that extended through the structure and was secured with a locking nut disposed within the system. It has been found that some designs of equipment will not provide sufficient access to secure a caster with a locking nut in this manner. In addition, such a locking nut makes it more difficult for field service personnel to assemble and service equipment at the customer site. There is therefore a need in the art for a caster attachment system that will allow the caster to be easily secured from the outside of the system.